extremely negative towards everyone, and never says anything nice. Whenever Duchess turns on the spot, her entire body pivots like a sheet of paper being flipped, revealing that she is two-dimensional. Her full name is "Her Royal Duchess Diamond Persnickety the First, Last, and Only". She speaks with a German accent. Details about Duchess's life before moving to Foster's or who created her remain a mystery since neither Duchess nor her creator were even shown at the reunion in "Good Wilt Hunting". Goo (voiced by Grey DeLisle) – A hyperactive, overly imaginative and talkative African-American girl who first appeared in "Go Goo Go". Her parents allowed her to name herself when she was a baby resulting in the full name "Goo Goo Ga Ga". Goo enjoys playing games such as Checkers and Truth or Dare, but she does not know how to play and Mac is the only one who notices. In her first appearance she constantly created friends because she had no real friends because of her odd behavior. She finally stopped making new friends and undoes them after Mac told her to get to know the ones she had made already. However, she has still created a few by mistake or to help on rare occasions. She is also shown to be friends with Cheese, as both of them get along because of their odd doings. Despite appearing older than Mac, her exact age has never been stated. Terrence (voiced by Tara Strong) – Mac's older brother and the recurring villain of the series. He enjoys bullying Mac and coming up with various schemes to make Mac's life hard and miserable. His stupidity always gets the better of him, making him easily outsmarted by Mac or Bloo. Cheese (voiced by Candi Milo) - The simple, dim-witted and pale yellow no. 0 imaginary friend who debuted in "Mac Daddy". Cheese was thought to be an imaginary friend accidentally created by Mac, but was actually created by Mac's neighbor Louise. He appears to be a nuisance and dim-witted, often saying incoherent or non-sequitur phrases, and breaking into sudden bouts of screaming when frightened or when he does not get his way. Cheese likes goldfish crackers, cereal, juice, chocolate milk (although he is lactose-intolerant), etc.. His real name is "Cheesus". In the series finale "Goodbye to Bloo", he becomes the newest resident at Foster's, much to the other residents' horror. Recurring